Coupling device

ABSTRACT

A unitized valve train assembly includes a finger follower having a pocket and a peripheral surface adjacent the pocket, and a hydraulic lash adjuster having a body, and a plunger extending from the body and received within the pocket of the finger follower. The plunger defines a longitudinal axis. The assembly also includes a single-wire coupling device having a first arm configured to selectively engage the finger follower, and a second arm clamped to one of the body and the plunger. The second arm is spaced from the peripheral surface of the finger follower when the plunger is received within the pocket of the finger follower.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationSer. No. 60/973,313 filed on Sep. 18, 2007, the entire content of whichis incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to couplings, and more particularly tocouplings for use in connecting valve train components of an engine.

BACKGROUND OF THE INVENTION

When creating an assembly of components, it is often desirable to createmultiple sub-assemblies, or “unitize” multiple individual components, tosimplify or facilitate the assembly process. A valve train of an engineincludes many components, and depending on the number of cylinders inthe engine, assembling all of the valve train components may require asignificant amount of time and precision when handling and connectingthe individual components.

SUMMARY OF THE INVENTION

Unitizing two or more valve train components in an engine can reduce theamount of time and precision required when handling and connecting theunitized components.

The present invention provides, in one aspect, a device adapted tocouple a finger follower and a hydraulic lash adjuster for use in avalve train of an engine. The hydraulic lash adjuster includes a plungerdefining a longitudinal axis. The finger follower includes a pocket forreceiving the plunger. The device includes a resilient clip having afirst arm configured to selectively engage the finger follower and asecond arm configured to receive the plunger of the hydraulic lashadjuster. The second arm of the clip includes a semi-circular or a hookportion that is engageable with the plunger from a directionsubstantially transverse to the longitudinal axis of the plunger.

The present invention provides, in another aspect, a device adapted tocouple a finger follower and a hydraulic lash adjuster for use in avalve train of an engine. The hydraulic lash adjuster includes a plungerdefining a longitudinal axis and a body that receives the plungertherein. The finger follower includes a pocket for receiving theplunger. The device includes a resilient clip having a first armconfigured to selectively engage the finger follower and a second armconfigured to receive the body of the hydraulic lash adjuster. Thesecond arm of the clip includes a substantially circular or hoop portionthat is engageable with the body of the hydraulic lash adjuster.

The present invention provides, in yet another aspect, a unitized valvetrain assembly including a finger follower having a pocket, a hydrauliclash adjuster having a plunger received within the pocket of the fingerfollower, and a device, such as the resilient clips described above,coupling the finger follower and the hydraulic lash adjuster.

The present invention provides, in a further aspect, a unitized valvetrain assembly includes a finger follower having a pocket and aperipheral surface adjacent the pocket, and a hydraulic lash adjusterhaving a body, and a plunger extending from the body and received withinthe pocket of the finger follower. The plunger defines a longitudinalaxis. The assembly also includes a single-wire coupling device having afirst arm configured to selectively engage the finger follower, and asecond arm clamped to one of the body and the plunger. The second arm isspaced from the peripheral surface of the finger follower when theplunger is received within the pocket of the finger follower.

The present invention provides, in another aspect, a unitized valvetrain assembly including a finger follower having a pocket, a hydrauliclash adjuster including a plunger received within the pocket of thefinger follower, the plunger defining a longitudinal axis, and acoupling device. The coupling device includes a first arm configured toselectively engage the finger follower, and a second arm including asubstantially semi-circular hook portion engageable with the plungerfrom a direction substantially transverse to the longitudinal axis ofthe plunger. The hook portion defines an inner diameter. The hookportion includes opposite ends defining therebetween a minimum gap lessthan the inner diameter of the hook portion.

The present invention provides, in yet another aspect, a single-wireresilient clip adapted to couple a finger follower and a hydraulic lashadjuster for use in a valve train of an engine. The hydraulic lashadjuster has a plunger defining a longitudinal axis, and the fingerfollower has a pocket for receiving the plunger. The resilient clipincludes a first arm configured to selectively engage the fingerfollower, and a second arm having a substantially semi-circular hookportion engageable with the plunger from a direction substantiallytransverse to the longitudinal axis of the plunger. The hook portiondefines an inner diameter. The hook portion includes opposite endsdefining therebetween a minimum gap less than the inner diameter of thehook portion.

The present invention provides, in a further aspect, a method ofcoupling a finger follower and a hydraulic lash adjuster for use in avalve train of an engine. The finger follower has a pocket for receivinga plunger of the hydraulic lash adjuster. The method includes providinga clip having a hook portion defining an inner diameter. The hookportion includes opposite ends defining therebetween a minimum gap lessthan the inner diameter of the hook portion. The method also includesinserting the plunger into the hook portion from a directionsubstantially transverse to a longitudinal axis of the plunger,spreading the opposite ends of the hook portion from each other duringinsertion of the plunger into the hook portion, clamping the plungerwith the hook portion to secure the clip to the hydraulic lash adjuster,and positioning the plunger within the pocket of the finger follower.

Other features and aspects of the invention will become apparent byconsideration of the following detailed description and accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side, partial cutaway view of a unitized valve trainassembly, including a first construction of a coupling device of thepresent invention coupling a roller finger follower and a hydraulic lashadjuster, assembled onto an engine.

FIG. 2 is an opposite side view of the unitized valve train assembly ofFIG. 1.

FIG. 3 is a side perspective view of the unitized valve train assemblyof FIG. 1.

FIG. 4 is an end perspective view of a portion of the unitized valvetrain assembly of FIG. 1.

FIG. 5 is an end view of the unitized valve train assembly of FIG. 1.

FIG. 6 is a bottom perspective view of a portion of the unitized valvetrain assembly of FIG. 1.

FIG. 7 is a side perspective view of the coupling device of the unitizedvalve train assembly of FIG. 1.

FIG. 8 is a side view of the coupling device of the unitized valve trainassembly of FIG. 1.

FIG. 9 is an end perspective view of the coupling device of the unitizedvalve train assembly of FIG. 1.

FIG. 10 is a side, partial cutaway view of a unitized valve trainassembly, including a second construction of a coupling device of thepresent invention coupling a roller finger follower and a hydraulic lashadjuster, assembled onto an engine.

FIG. 11 is an opposite side view of the unitized valve train assembly ofFIG. 10.

FIG. 12 is a side perspective view of the unitized valve train assemblyof FIG. 10.

FIG. 13 is a top perspective view of the unitized valve train assemblyof FIG. 10.

FIG. 14 is an end view of a portion of the unitized valve train assemblyof FIG. 10.

FIG. 15 is a top perspective view of a portion of the unitized valvetrain assembly of FIG. 10.

FIG. 16 is a side perspective view of the unitized valve train assemblyof FIG. 10.

FIG. 17 is a side perspective view of the coupling device of theunitized valve train assembly of FIG. 10.

FIG. 18 is an end perspective view of the coupling device of theunitized valve train assembly of FIG. 10.

FIG. 19 is a front perspective view of a plunger of a hydraulic lashadjuster of the unitized valve train assembly of FIGS. 1 and 10.

FIG. 20 is a side view of the unitized valve train assembly of FIG. 1prior to engine assembly.

FIG. 21 is an opposite side view of the unitized valve train assembly ofFIG. 1

FIG. 22 is a side view of the unitized valve train assembly of FIG. 10prior to engine assembly.

FIG. 23 is a top perspective view of the unitized valve train assemblyof FIG. 10 prior to engine assembly.

Before any embodiments of the invention are explained in detail, it isto be understood that the invention is not limited in its application tothe details of construction and the arrangement of components set forthin the following description or illustrated in the following drawings.The invention is capable of other embodiments and of being practiced orof being carried out in various ways. Also, it is to be understood thatthe phraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. The use of“including,” “comprising,” or “having” and variations thereof herein ismeant to encompass the items listed thereafter and equivalents thereofas well as additional items. Unless specified or limited otherwise, theterms “mounted,” “connected,” “supported,” and “coupled” and variationsthereof are used broadly and encompass both direct and indirectmountings, connections, supports, and couplings. Further, “connected”and “coupled” are not restricted to physical or mechanical connectionsor couplings.

DETAILED DESCRIPTION

FIGS. 1-6 illustrate a unitized valve train assembly 10 including arocker arm or a spherical-end pivoting, roller cam follower assembly orroller finger follower 14, a hydraulic lash adjuster (“HLA”) 18, and acoupling device 22 for unitizing or coupling the follower 14 and the HLA18. The follower 14 includes a ball socket having a pocket 24 in whichthe spherical-pivot component of the HLA, customarily the piston orplunger 26, is received. A similar follower 14 is shown in published PCTPatent Application No. WO 2008/002746, the entire content of which isincorporated herein by reference. The HLA 18 includes a housing or body30 in which the plunger 26 is supported, and the plunger 26 includes ashank 34 and a spherical end portion 38 which engages the pocket 24 ofthe follower 14 (see FIG. 19). Such a unitized valve train assembly 10may be used, for example, in an engine having an overhead camshaftconfiguration. FIGS. 1-3 illustrate a cam lobe 42 of an overheadcamshaft actuating the follower 14 and a corresponding valve 46.

With reference to FIGS. 1-6, the body 30 of the HLA 18 includes a cap 50crimped to the upper portion of the body 30, thereby forming anintegrated part of the body 30. As is known in the art, the cap 50axially secures the plunger 26 within the body 30 and limits the axialextent to which the plunger 26 can extend from the body 30. Also, asshown in FIG. 19, the plunger 26 of the HLA 18 is configured with anundercut 54, a portion of which is defined by the shank 34.Alternatively, the plunger 26 of the HLA 18 may be configured without anundercut. Such a plunger without an undercut is shown and described inpublished PCT Patent Application No. WO 2008/002746.

With reference to FIGS. 7-9, the coupling device 22 is comprised of aclip 58 made from a single piece of resilient material (e.g., steelwire) that is bent or otherwise formed into the illustrated shape. Insome constructions of the clip 58, the steel wire utilized to form theclip 58 has a diameter between about 0.5 and about 0.75 mm.Alternatively, other wire diameters may be utilized depending on thesizing of the other valve train components. The wire diameter utilizedto form the clip 58 also affects the positional tolerance where the clip58 may be attached to the plunger shank 34. The clip 58 should besecured to the plunger shank 34 in an axial position on the plungershank 34 in which no portion of the clip 58 substantially interfereswith movement of the plunger 26 or the follower 14 during operation ofthe engine. As such, decreasing the wire diameter of the clip 58proportionally increases the positional tolerance where the clip 58 maybe attached to the plunger shank 34.

The clip 58 includes a first or upper arm 62 selectively engageable withthe follower 14, a second or lower arm 66 configured to engage and clamponto the plunger 26, and an intermediate portion 70 interconnecting theupper and lower arms 62, 66. The upper arm 62 of the clip 58 isconfigured to extend around the ball socket of the follower 14 (seeFIGS. 1 and 2). Specifically, the upper arm 62 includes an arcuate lipportion 74 engageable with the ball socket of the follower 14 tofacilitate the connection of the clip 58 and the follower 14, and toprovide resistance to the disconnection of the clip 58 and the follower14.

In the illustrated construction of the clip 58 in FIG. 7, the lower arm66 of the clip 58 includes a semi-circular portion or a hook portion 78having opposite ends 82 a, 82 b and a splayed end portion 86 disposedtoward the distal end of the hook portion 78. The hook portion 78 of theclip 58 includes an inner diameter D1 less than the outer diameter D2 ofthe plunger shank 34 (see FIG. 19), resulting in an interference fitbetween the clip 58 and the plunger shank 34 when the hook portion 78 ofthe clip 58 is engaged or clamped to the plunger shank 34. Such aninterference fit substantially prevents the lower arm 66 of the clip 58from rotating, pivoting, or rocking with respect to the plunger 26during operation of the engine. In some constructions of the clip 58,the interference between the inner diameter D1 of the hook portion 78and the outer diameter D2 of the plunger shank 34 may be between about1% and about 8% of the outer diameter D2 of the plunger shank 34. Inother words, the inner diameter D1 of the hook portion 78 may be betweenabout 92% and about 99% of the outer diameter D2 of the plunger shank34. Alternatively, in other constructions of the clip 58, theinterference between the inner diameter D1 of the hook portion 78 andthe outer diameter D2 of the plunger shank 34 may be about 4% of theouter diameter D2 of the plunger shank 34.

In addition, the respective ends 82 a, 82 b of the hook portion 78, whenthe clip 58 is removed from the plunger shank 34 and when the clip 58 isin its undeformed or undeflected state, may be spaced by a length or gapdimension D3 less than the outer diameter D2 of the plunger shank 34. Insome constructions of the clip 58, the gap dimension D3 may be betweenabout 5% and about 13% less than the outer diameter D2 of the plungershank 34 when the clip 58 is removed from the plunger shank 34 and whenthe clip 58 is in its undeformed or undeflected state.

FIGS. 1-6 illustrate the clip 58 attached to the HLA 18. To preassemblethe clip 58 and the HLA 18, the hook portion 78 is axially aligned withthe plunger 26 and the clip 58 is moved toward the plunger 26 in adirection substantially transverse to a central axis 90 of the plunger26 (see FIG. 19). After initial engagement of the splayed end portion 86of the clip 58 and the end 82 a of the hook portion 78, continuedmovement of the clip 58 in a direction substantially transverse to thecentral axis 90 of the plunger 26 causes the respective ends 82 a, 82 bof the hook portion 78 to separate as the plunger shank 34 is insertedbetween the ends 82 a, 82 b of the hook portion 78.

After the respective ends 82 a, 82 b of the hook portion 78 pass “overcenter” of the plunger shank 34—i.e., immediately after the respectiveends 82 a, 82 b of the hook portion 78 are spread such that the gapdimension D3 is substantially equal to the outer diameter D2 of theplunger shank 34—the hook portion 78 snaps onto the plunger shank 34 tosecure the clip 58 to the plunger 26. With reference to FIG. 6, afterthe clip 58 is engaged or clamped to the plunger shank 34, the gapdimension D3 between the respective ends 82 a, 82 b of the hook portion78 is greater than the gap dimension D3 when the clip 58 is removed fromthe plunger shank 34. Specifically, in some constructions of the clip58, the gap dimension D3 between the respective ends 82 a, 82 b of thehook portion 78 after the clip 58 is engaged to the plunger shank 34 isabout 2% to about 5% less than the outer diameter D2 of the plungershank 34. Because the hook portion 78 of the clip 58 cannot fully returnto its undeformed or undeflected state shown in FIGS. 7 and 9 after itis engaged with the plunger shank 34, a clamping force is exerted on theplunger shank 34 by the hook portion 78 sufficient to generatefrictional forces on the plunger shank 34 along and about the centralaxis 90 of the plunger 26 to substantially prevent the hook portion 78from rotating, pivoting, or rocking with respect to the plunger shank 34during operation of the engine.

However, the clip 58 may co-rotate with the plunger 26 with respect tothe plunger body 30 and the follower 14. As shown in FIG. 5, theintermediate portion 70 of the clip 58 may come into contact with a sidewall of the follower 14 should the plunger 26 and the clip 58 co-rotateabout the central axis 90 during operation of the engine. As such, theside walls of the follower 14 limit the extent to which the plunger 26and the clip 58 may co-rotate during operation of the engine.

After the clip 58 is secured to the HLA 18, the unitized clip 58 and HLA18 may be assembled onto the follower 14 in substantially the samefashion as disclosed in published PCT Patent Application No. WO2008/002746. The follower 14 may initially be oriented such that itspocket 24 may receive the spherical end portion 38 of the plunger 26. Asthe spherical end portion 38 of the plunger 26 is inserted into thepocket 24 of the follower 14, the arcuate lip portion 74 of the upperarm 62 may engage an upper surface of the follower 14, causing the clip58 to deflect or elastically bend to an “open” position to complete theinsertion of the spherical end portion 38 of the plunger 26 in thepocket 24 of the follower 14. After the pocket 24 of the follower 14receives the spherical end portion 38 of the plunger 26, the clip 58will resume its undeflected shape or its “closed” position to secure thefollower 14 to the HLA 18, as shown in FIGS. 1-6.

Alternatively, the follower 14 and the HLA 18 may be pre-assembled bypositioning the spherical end portion 38 of the plunger 26 into thepocket 24 of the follower 14, and the clip 58 may be brought in from theside of the pre-assembled follower 14 and HLA 18, in a directionsubstantially transverse to the central axis 90 of the plunger 26, toengage the hook portion 78 of the clip 58 and the plunger shank 34.Depending on the orientation of the follower 14, the upper arm 62 may ormay not be deflected to clear the side wall of the follower 14 uponattachment of the clip 58 in this manner.

The follower 14 and HLA 18 can now be handled as a unit, withoutsubstantial concern that the HLA 18 may be unintentionally separatedfrom the follower 14. To separate the HLA 18 and the follower 14, thearcuate lip portion 74 must be forced to pass over the upper surface ofthe follower 14, thereby causing the clip 58 to deflect back to its“open” position to allow removal of the spherical end portion 38 of theplunger 26 from the pocket 24. The resilient property of the clip 58allows it to be bent slightly to permit insertion and removal of thefollower 14 between the upper arm 62 of the clip 58 and the sphericalend portion 38 of the plunger 26 without permanently distorting the clip58 to the extent that its retention is substantially compromised.

When installed in an engine application, sufficient clearance isprovided by the geometry of the clip 58 such that the follower 14 isable to pivot on the spherical end portion 38 of the plunger 26 throughthe necessary range of operating angles without causing damage to orbinding of any components, including the follower 14 and the HLA 18themselves, due to interference. Specifically, the arm 66 is positionedon the plunger shank 34 such that it is spaced, in a direction parallelto the longitudinal axis 90, from a bottom surface of the follower 14,and particularly a peripheral surface 92 adjacent the pocket 24, toprevent binding between the clip 58 and the follower 14. In addition,the arm 66 is positioned on the plunger shank 34 such that it is spaced,in a direction parallel to the longitudinal axis 90, from the cap 50 ofthe HLA 18 to prevent binding between the clip 58 and the HLA 18.

The clip 58 facilitates handling of the follower 14 and the HLA 18 as aunit, without substantial concern that the follower 14 and the HLA 18may become unintentionally separated, without requiring any specialfeatures on either the follower 14 or the HLA 18, such as an undercut ofthe plunger shank 34, and without impeding the intended motion of eitherthe follower 14 or the HLA 18, particularly the rotation of the plunger26 in the body 30. FIGS. 20 and 21 illustrate the unitized valve trainassembly 10 prior to engine installation. The clip 58 maintains thespherical end portion 38 of the plunger 26 at least partially within thepocket 24 of the follower 14 when only the follower 14 is grasped andpicked up. In some constructions of the clip 58, the arcuate lip portion74 may be spaced from the upper surface of the ball socket of thefollower 14 by as much as about 2 mm to about 3 mm to allow sufficientplay between the HLA 18 and the follower 14 yet prevent the HLA 18 fromunintentionally disengaging and separating from the follower 14.Alternatively, depending on the sizing of the other valve traincomponents, more or less spacing between the arcuate lip portion 74 andthe upper surface of the follower ball socket may be utilized.

Once installed in a fully assembled engine, the clip 58 is no longerneeded to keep the follower 14 assembled to the HLA 18. Rather, the clip58 is only needed to keep the follower 14 from unintentionallyseparating from the HLA 18 when the engine is only partially assembled.Therefore, during operation of the fully assembled engine, little or nocontact between the upper surface of the follower ball socket and theunderside of the upper arm 62 or the arcuate lip portion 74 occursbecause repeated contact may lead to wear or breakage of the clip 58.Contact between the upper surface of the ball socket and the undersideof the upper arm 62 or the arcuate lip portion 74 usually only occursduring assembly, either when the follower 14 is installed onto the HLA18, or when the follower 14 is being prevented from unintentionallyseparating from the HLA 18 during handling of the unitized valve trainassembly 10.

FIGS. 10-16 illustrate a unitized valve train assembly 94 includinganother construction of the coupling device 98. Like components arelabeled with like reference numerals. Generally, rather than beingsecured to the plunger 26 of the HLA 18, the coupling device 98 issecured to the body 30 of the HLA 18.

With reference to FIGS. 17 and 18, the coupling device 98 comprises aclip 102 made from a single piece of resilient material (e.g., steelwire) that is bent or otherwise formed in symmetrical halves about aplane containing the central axis 90 of the HLA 18. In someconstructions of the clip 102, the steel wire utilized to form the clip102 has a diameter between about 0.5 mm and about 0.75 mm.Alternatively, other wire diameters may be utilized depending on thesizing of the other valve train components, and the spacing between thebody 30 of the HLA 18 and the follower 14.

The clip 102 includes a first or upper portion 106 selectivelyengageable with the follower 14, a second or lower portion 110configured to engage the body 30 of the HLA 18, and an intermediateportion 114 interconnecting the upper and lower portions 106, 110. Theupper portion 106 and the intermediate portion 114 of the clip 102 eachinclude dual parallel segments 118 of the wire that extend from the hoopportion 126. Each wire segment 118 comprising the upper portion 106 alsoincludes a splayed distal end 122 selectively engageable with the ballsocket of the follower 14 to facilitate the connection of the clip 102and the follower 14, and to provide resistance to the disconnection ofthe clip 102 and the follower 14.

In the illustrated construction of the clip 102 in FIG. 17, the lowerportion 110 of the clip 102 includes a circular portion or a hoopportion 126 having an inner diameter D4 less than the outer diameter D5of the cap 50 of the HLA 18 (see FIG. 14), resulting in an interferencefit between the clip 102 and the body 30 when the hoop portion 126 ofthe clip 102 is engaged to the body 30. Such an interference fitsubstantially prevents the lower portion 110 of the clip 102 fromrotating, pivoting, or rocking with respect to the body 30 duringoperation of the engine. In some constructions of the clip 102, in itsundeformed or undeflected state, the hoop portion 126 of the clip 102may have a diameter D4 between about 5% and about 10% less than theeffective diameter D5 of the cap 50 to yield the interference fitbetween the clip 102 and the body 30. Alternatively, the clip 102 may beconfigured with only a single wire segment comprising the intermediateportion 114 of the clip 102, and only a single wire segment comprisingthe upper portion 106 of the clip 102.

FIGS. 10-16 illustrate the clip 102 attached or clamped to the HLA 18.To preassemble the clip 102 and the HLA 18, the hoop portion 126 of theclip 102 is aligned with the central axis 90 of the plunger 26, theplunger 26 is inserted through the hoop portion 126, and the individualwire segments 118 comprising the upper and intermediate portions 106,114 of the clip 102 are spread apart to receive the body 30 of the HLA18. Specifically, the wire segments 118 are spread apart to allow thehoop portion 126 to move over the cap 50, after which the wire segments118 may be released to allow the clip 102 to clamp onto the cap 50 oranother portion of the body 30.

Because the hoop portion 126 of the clip 102 cannot fully return to itsundeformed or undeflected state shown in FIGS. 17 and 18 after it isengaged with the body 30, a clamping force is exerted on the body 30 bythe hoop portion 126 of the clip 102 sufficient to generate frictionalforces on the body 30 along and about the central axis 90 of the plunger26 to substantially prevent the hoop portion 126 of the clip 102 fromrotating, pivoting, or rocking with respect to the body 30 duringoperation of the engine.

Assembly of the unitized clip 102 and HLA 18 may occur in substantiallythe same fashion as described above and as disclosed in published PCTPatent Application No. WO 2008/002746. FIGS. 22 and 23 illustrate theunitized valve train assembly 94 prior to engine installation. Thediscussion above relating to the unitized valve train assembly 10 inFIGS. 20 and 21 also applies to the unitized valve train assembly 94 inFIGS. 22 and 23. Like the clip 58 discussed above, the arm 110 ispositioned on the cap 50 such that it is spaced, in a direction parallelto the longitudinal axis 90, from the bottom surface of the follower 14,and particularly the peripheral surface 92 adjacent the pocket 24, toprevent binding between the clip 102 and the follower 14.

Various features of the invention are set forth in the following claims.

1. A unitized valve train assembly comprising: a finger followerincluding a pocket and a peripheral surface adjacent the pocket; ahydraulic lash adjuster including a body; and a plunger extending fromthe body and received within the pocket of the finger follower, theplunger defining a longitudinal axis; a single-wire coupling deviceincluding a first arm configured to selectively engage the fingerfollower; and a second arm clamped to one of the body and the plunger;wherein the second arm is spaced from the peripheral surface of thefinger follower when the plunger is received within the pocket of thefinger follower.
 2. The unitized valve train assembly of claim 1,wherein the second arm includes a substantially semi-circular hookportion clamped to the one of the body and the plunger from a directionsubstantially transverse to the longitudinal axis of the plunger.
 3. Theunitized valve train assembly of claim 2, wherein the hook portiondefines an inner diameter, and wherein the hook portion includesopposite ends defining therebetween a minimum gap less than the innerdiameter of the hook portion.
 4. The unitized valve train assembly ofclaim 3, wherein the plunger defines an outer diameter greater than theinner diameter of the hook portion prior to clamping the hook portion tothe plunger.
 5. The unitized valve train assembly of claim 4, wherein adifference between the inner diameter of the hook portion and the outerdiameter of the plunger yields an interference between about 1% andabout 8% of the outer diameter of the plunger.
 6. The unitized valvetrain assembly of claim 3, wherein the plunger defines an outer diametergreater than the gap between the respective ends of the hook portionprior to clamping the hook portion to the plunger, and wherein therespective ends of the hook portion spread apart from each other duringclamping of the hook portion to the plunger.
 7. The unitized valve trainassembly of claim 6, wherein the gap between the respective ends of thehook portion prior to clamping the hook portion to the plunger isbetween about 5% and about 13% less than the outer diameter of theplunger.
 8. The unitized valve train assembly of claim 2, wherein thehook portion is clamped to the plunger, and wherein the hook portion isspaced from the body when the plunger is received within the pocket ofthe finger follower.
 9. The unitized valve train assembly of claim 2,wherein the plunger includes a shank and a spherical end portion, andwherein the hook portion is clamped to the shank.
 10. The unitized valvetrain assembly of claim 9, wherein the first arm includes an arcuate lipportion configured to selectively engage the finger follower.
 11. Theunitized valve train assembly of claim 9, wherein at least a portion ofthe shank is cylindrical, and wherein substantially the entire length ofthe hook portion is engageable with the cylindrical portion of theshank.
 12. The unitized valve train assembly of claim 1, wherein thecoupling device is formed from a single wire having a circularcross-sectional shape.
 13. The unitized valve train assembly of claim12, wherein the single wire has a diameter between about 0.5 mm andabout 0.75 mm.
 14. The unitized valve train assembly of claim 1, whereinthe second arm includes a hoop portion clamped to the body.
 15. Theunitized valve train assembly of claim 14, wherein the first armincludes dual, parallel wire segments, and wherein the coupling devicefurther includes dual, parallel intermediate wire segmentsinterconnecting the hoop portion and the respective wire segments of thefirst arm.
 16. A unitized valve train assembly comprising: a fingerfollower including a pocket; a hydraulic lash adjuster including aplunger received within the pocket of the finger follower, the plungerdefining a longitudinal axis; a coupling device including a first armconfigured to selectively engage the finger follower; and a second armincluding a substantially semi-circular hook portion engageable with theplunger from a direction substantially transverse to the longitudinalaxis of the plunger; wherein the hook portion defines an inner diameter,and wherein the hook portion includes opposite ends definingtherebetween a minimum gap less than the inner diameter of the hookportion.
 17. The unitized valve train assembly of claim 16, wherein theplunger defines an outer diameter greater than the gap between therespective ends of the hook portion prior to assembly of the hydrauliclash adjuster and the coupling device, and wherein the respective endsof the hook portion spread apart from each other during assembly of thehydraulic lash adjuster and the coupling device.
 18. The unitized valvetrain assembly of claim 17, wherein the gap between the respective endsof the hook portion prior to assembly of the hydraulic lash adjuster andthe coupling device is between about 5% and about 13% less than theouter diameter of the plunger.
 19. A single-wire resilient clip adaptedto couple a finger follower and a hydraulic lash adjuster for use in avalve train of an engine, the hydraulic lash adjuster having a plungerdefining a longitudinal axis, the finger follower having a pocket forreceiving the plunger, the resilient clip comprising: a first armconfigured to selectively engage the finger follower; and a second armincluding a substantially semi-circular hook portion engageable with theplunger from a direction substantially transverse to the longitudinalaxis of the plunger; wherein the hook portion defines an inner diameter,and wherein the hook portion includes opposite ends definingtherebetween a minimum gap less than the inner diameter of the hookportion.
 20. The single-wire resilient clip of claim 19, wherein thefirst arm includes an arcuate lip portion configured to selectivelyengage the finger follower.
 21. The single-wire resilient clip of claim19, further comprising an intermediate portion interconnecting the firstand second arms, wherein the intermediate portion is orientedsubstantially normal to the first arm and the second arm.
 22. A methodof coupling a finger follower and a hydraulic lash adjuster for use in avalve train of an engine, the finger follower having a pocket forreceiving a plunger of the hydraulic lash adjuster, the methodcomprising: providing a clip having a hook portion defining an innerdiameter, the hook portion including opposite ends defining therebetweena minimum gap less than the inner diameter of the hook portion;inserting the plunger into the hook portion in a direction substantiallytransverse to a longitudinal axis of the plunger; spreading the oppositeends of the hook portion from each other during insertion of the plungerinto the hook portion; clamping the plunger with the hook portion tosecure the clip to the hydraulic lash adjuster; and positioning theplunger within the pocket of the finger follower.
 23. The method ofclaim 22, further comprising: providing a first arm on the clip havingthe hook portion; providing a second arm on the clip spaced from thefirst arm; and supporting the hydraulic lash adjuster from the fingerfollower via engagement of the first arm and the finger follower.